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The first logic gate to operate at femtosecond timescales could help usher in an era of information processing at petahertz frequencies – a million times faster than today’s gigahertz-scale computers. The new gate, developed by researchers at the University of Rochester in the US and the Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) in Germany, is an application of lightwave electronics – essentially, shuffling electrons around with light fields – and harnesses both real and virtual charge carriers.

In lightwave electronics, scientists use laser light to guide the motion of electrons in matter, then exploit this control to create electronic circuit elements. “Since light oscillates so fast (roughly a few hundred million times per second), using light could speed up electronics by a factor of roughly 10 000 as compared to computer chips,” says Tobias Boolakee, a laser physicist in Peter Hommelhoff’s group at the FAU and the first author of a study in Nature on the new gate. “With our present work, we have been able propose the idea for a first light field-driven logic gate (the fundamental building block for any computer architecture) and also demonstrate its working principle experimentally.”

In the work, Boolakee and colleagues prepared tiny graphene-based wires connected to two gold electrodes and illuminated them with a laser pulse lasting a few tens of femtoseconds (10-15 s). This laser pulse excites, or sets in motion, the electrons in graphene and causes them to propagate in a particular direction – so generating a net electrical current.

The differences? The new Mayflower—logically dubbed the Mayflower 400—is a 50-foot-long trimaran (that’s a boat that has one main hull with a smaller hull attached on either side), can go up to 10 knots or 18.5 kilometers an hour, is powered by electric motors that run on solar energy (with diesel as a backup if needed), and required a crew of… zero.

That’s because the ship was navigated by an on-board AI. Like a self-driving car, the ship was tricked out with multiple cameras (6 of them) and sensors (45 of them) to feed the AI information about its surroundings and help it make wise navigation decisions, such as re-routing around spots with bad weather. There’s also onboard radar and GPS, as well as altitude and water-depth detectors.

The ship and its voyage were a collaboration between IBM and a marine research non-profit called ProMare. Engineers trained the Mayflower 400’s “AI Captain” on petabytes of data; according to an IBM overview about the ship, its decisions are based on if/then rules and machine learning models for pattern recognition, but also go beyond these standards. The algorithm “learns from the outcomes of its decisions, makes predictions about the future, manages risks, and refines its knowledge through experience.” It’s also able to integrat e far more inputs in real time than a human is capable of.

Leading bipartisan moonshots for health, national security & functional government — senator joe lieberman, bipartisan commission on biodefense, no labels, and the centre for responsible leadership.


Senator Joe Lieberman, is senior counsel at the law firm of Kasowitz Benson Torres (https://www.kasowitz.com/people/joseph-i-lieberman) where he currently advises clients on a wide range of issues, including homeland and national security, defense, health, energy, environmental policy, intellectual property matters, as well as international expansion initiatives and business plans.

Prior to joining Kasowitz, Senator Lieberman, the Democratic Vice-Presidential nominee in 2000, served 24 years in the United States Senate where he helped shape legislation in virtually every major area of public policy, including national and homeland security, foreign policy, fiscal policy, environmental protection, human rights, health care, trade, energy, cyber security and taxes, as well as serving in many leadership roles including as chairman of the Committee on Homeland Security and Government Affairs.

Stacking solar cells increases their efficiency. Working with partners in the PERCISTAND project, researchers at the Karlsruhe Institute of Technology (KIT) have produced perovskite/CIS tandem solar cells with an efficiency of nearly 25%—the highest value achieved thus far with this technology. Moreover, this combination of materials is light and versatile, making it possible to envision the use of these tandem solar cells in vehicles, portable equipment, and devices that can be folded or rolled up. The researchers present their results in the journal ACS Energy Letters.

Perovskite have made astounding progress over the past decade. Their efficiency is now comparable to that of the long-established silicon solar cells. Perovskites are innovative materials with a special crystal structure. Researchers worldwide are working to get photovoltaic technology ready for practical applications. The more electricity they generate per unit of surface area, the more attractive solar cells are for consumers.

The efficiency of solar cells can be increased by stacking two or more cells. If each of the stacked solar cells is especially efficient at absorbing light from a different part of the solar spectrum, inherent losses can be reduced and efficiency boosted. The efficiency is a measure of how much of the is converted into electricity. Thanks to their versatility, perovskite solar cells make outstanding components for such tandems. Tandem solar cells using perovskites and silicon have reached a record efficiency level of over 29%, considerably higher than that of made of perovskite (25.7%) or silicon (26.7%).

“Blinking” behavior of fluorophores, being harmful for the majority of super-resolved techniques, turns into a key property for stochastic optical fluctuation imaging and its modifications, allowing one to look at the fluorophores already used in conventional microscopy, such as graphene quantum dots, from a completely new perspective. Here we discuss fluorescence of aggregated ensembles of graphene quantum dots structured at submicron scale. We study temperature dependence and stochastic character of emission. We show that considered quantum dots ensembles demonstrate rather complicated temperature-dependent intermittent emission, that is, “blinking” with a tendency to shorten “blinking” times with the increase of temperature.

Summary: Administering oxytocin to influential members of a social network helped increase overall group cooperation.

Source: SfN

Administering oxytocin to the central members of a social network spreads cooperation via increased punishment of uncooperative behavior, according to new research published in Journal of Neuroscience.

Operators of the ALICE detector have observed the first direct evidence of the “dead cone effect,” allowing them to assess the mass of the elusive charm quark.


The ALICE collaboration at the Large Hadron Collider (LHC) in Geneva, Switzerland, recently made the first observation of an important aspect of particle physics called the “dead cone effect.”

The effect is a fundamental element of the strong nuclear force — one of the four fundamental forces of nature — responsible for binding quarks and gluons. These are the fundamental particles that comprise hadrons, such as protons and neutrons, that in turn make up all atomic nuclei, which are never seen on their own under normal circumstances, only at the kind of high energy levels generated at the LHC.

“We made a direct observation of an effect in the theory of the strong force called the dead-cone effect,” experimental high energy physicist at CERN, Nima Zardoshti, tells Popular Mechanics. “This is a part of the theory that had been predicted for a while but had not been directly observed until now.”